1. Field of the Invention
This invention relates to peer-to-peer networking, and more particularly to a system and method for the secure exchange of messages and other data between peers in a peer-to-peer environment.
2. Description of the Related Art
The term peer-to-peer (also referred to as P2P) networking may be applied to a wide range of technologies that greatly increase the utilization of information, bandwidth, and computing resources in the Internet. Frequently, these P2P technologies adopt a network-based computing style that neither excludes nor inherently depends on centralized control points. Apart from improving the performance of information discovery, content delivery, and information processing, such a style also can enhance the overall reliability and fault-tolerance of computing systems. The peer-to-peer model may also help to reduce the load on server systems by allowing peers to bypass the server for information, file exchange, and some resource sharing, allowing the servers to perform services which require the specialized hardware and/or software of a “dedicated” server system.
FIGS. 1A and 1B are examples illustrating the peer-to-peer model. FIG. 1A shows two peer devices 104A and 104B that are currently connected. Either of the two peer devices 104 may serve as a client of or a server to the other device. FIG. 1B shows several peer devices 104 connected over the network 106 in a peer group. In the peer group, any of the peer devices 104 may serve as a client of or a server to any of the other devices.
On the Internet, peer-to-peer may refer to a type of transient network that allows a group of computer users (peers) to connect with each other and directly access resources from one another's computer systems. Resources may include, but are not limited to, hardware and software resources such as files, disks, chat messages, applications, and printers, among others. A user must first download and execute the peer-to-peer networking program. After launching the program, the user enters the address (e.g. IP address) of another computer belonging to the network. Once the computer finds another network member on-line, it may connect to that user's connection (who has gotten their IP address from another user's connection and so on). Users may choose how many member connections to seek at one time and determine which resources (e.g. files) they wish to share or password protect. Napster and Gnutella are examples of this kind of peer-to-peer software.
On the Internet, “chat” may refer to two or more users “talking” over the Internet by exchanging messages while using the Internet at the same time. Chatting may involve the exchange of typed-in messages requiring one site as the repository for the messages (or “chat site”) and a group of users who take part from anywhere on the Internet. Chats may be conducted on online services (e.g. America Online), by bulletin board services, and by Web sites, for example. Several Web sites, e.g. Talk City, exist solely for the purpose of conducting chats. Talk City and many other chat sites use a protocol called Internet Relay Chat. Alternatively, some peer-to-peer platforms may provide a mechanism for users to join in a chat session and exchange messages or other data directly without requiring one site as a message repository.
Prior to the development of the peer-to-peer model, computer users' systems connected to the Internet were typically relegated to being clients in a client/server model. When operating in some peer-to-peer models on the Internet or other networks, a peer system may operate outside of the Domain Name System (DNS), and thus may operate independently from the client/server model of the network that may include DNS servers and other servers. In a peer-to-peer network, a peer device or node, which may be referred to simply as a “peer,” may bypass servers to remotely access resources (e.g. files) and information from other peers. Peers in the peer-to-peer network typically may share information and resources with other peers, and may exchange and search for information and resources on a network of users (peers) with common interests. Peers in a peer-to-peer network may also participate in “chat” by exchanging messages.
Public Key/Private Key Encryption
A public key may be defined as a value, provided by some designated, trusted authority, that, combined with a private key derived from the public key (or vice versa), can be used to effectively encrypt and decrypt messages and other data (e.g. files), and that may also be used as a digital signature. A public and private key may be created, in some instances simultaneously, using the same algorithm. A popular algorithm for generating public/private keys is the RSA (Rivest-Shamir-Adleman) algorithm. Other algorithms may also be used, such as TLS (Transport Layer Security). The use of combined public and private keys is known as asymmetric cryptography. Given a private key it is computationally infeasible to determine the public key (and vice-versa).
In a peer-to-peer network, two or more peers may desire to exchange secured messages, for example during a chat session. A peer in a peer-to-peer network may also desire to securely provide resources such as files or other data to one or more other peers. Thus, it may be desirable to provide a method for peers to exchanges messages and/or data, for example using public key/private key encryption. However, since peers in the peer-to-peer network may operate outside of the DNS and independently from the client/server model, typically there is no central server or authority to manage security, specifically public key/private key encryption, for peer groups such as the groups illustrated in FIGS. 1A and 1B. Therefore, it may be desirable to provide a method for peers in a peer-to-peer network to participate in secured message and/or data exchange independent of a central security authority.